Knitted fabric and method of making the same



Aug. 22, 1950 F. Y. NAKAYAMA KNITTED FABRIC AND METHOD OF MAKING THESAME Filed May 10, 1948 FRANK Y. NAKAYAMA ATTORNEY Patented Aug. 22,1950 KNITTED FABRIC AND METHOD OF MAKING THE SAIVIE Frank Y. Nakayama,Seattle, Wash., assignor to C. T. Takahashi, Seattle, Wash.

Application May 10, 1948, Serial No. 26,011

3 Claims.

This invention relates to the art of knitted fabrics, and for itsprincipal object aims to provide a textile containing within thecomposition of its yarns aconsiderable quantity of kapok fibers, thusmaking available to the knitting industry a plentiful and, by presentstandards, an unusually low-cost material for use in the production ofknitted fabrics.

The textile industry, while it has long recognized the many desirablequalities which are peculiar to kapok and has exerted considerableeffort toward adapting fibers of the same to use in fabrics, has nowlargely abandoned experimentation with this material and the sameconsequently still finds commercial usage primarily only for packingpurposes and as a fill ingredient for pillows and the like. One of theobstacles to usage in fabrics which, prior to the present invention, hasbeen deemed insurmountable is the highly brittle nature of the rawfibers and the industry has arrived at the unwarranted conclusion thatthe fibers would necessarily break when subjected to fiexure andfurthermore, in their resistance to curling, would give to the producedfabric a rough and scratchy feeling. There has also been this furtherobjection, and that is the constituent wax contained in the fibers ofkapok, causing the fibers to slip and making it diflicult to anchor thesame within a woven body. All of these obstacles are effectively met andquite simply overcome in the instant process.

According to the present invention, and having reference to theaccompanying drawing where I have illustrated a cross-section through apiece of double-faced knitting to schematically portray successivelypracticed steps of a suitable process, the procedure is to employ threeyarns each of which contain staple fibers, as cotton, wool, rayon or thelike, mixed in each instance with kapok fibers. proportion is or may be20% or thereabouts of kapok fibers. The third said yarn contains kapokfibers in the proportion, say, of one-half kapok to one-half basicmaterials. Using a knitting machine of the usual suitable construction,yarns 5 and 6 from two spools, each containing 20% kapok, are knit intoloops on both sides of the fabric to form, in the instance of each yarn,a ply that interengages with the ply formed by the other of the twoyarns. The third yarn, denoted by I, is incorporated unknit as an inlayyarn. When the knitting has been completed, the produced textile is thenprocessed by subjecting the same to heat and moisture, accomplishedeither by subjecting the textile to a. steam In two of these yarns, the

treatment or by dipping the same into boiling water. This treatmentaccomplishes two important ends, it extracts from the kapok fibers apart of the constituent wax and so softens the fibers as to permit thesame to be easily bent.

The final step in the process, after this heat and moisture treatment,is to raise the fibers from the base of the knitting, and thisoperation, which in and of itself is common practice with ordinary yarnsand may be performed by any one of a number of thread-picking machinesexpressly designed for the purpose, causes the kapok strands to be eachdrawn out from the knitting base at spaced intervals of their length.Insofar as each individual fiber is concerned, the same will be drawnout from the knitting base in a plurality of looping curls and with thefibers perforce piercing the knitting base between each said curl, eachfiber usually piercing the base three times. A representation ofindividual raised fibers is shown at 8 and, by cumulation, there isproduced in the finished product such an abundance of closely associatedraised curls, denoted at H], as to substantially pack the gaps of theknitting base and there results a textile having much the sameappearance and the velvety feel of a raised virgin-wool blanket. Despitethe abundant content of kapok fibers, the latter do not wear down easilynor do the pertions thereof which pierce the knitting base tend to slip,hence substantially negating any slufling of the fibers.

Kapok, when it is adapted to use in textiles through a knitting processsuch as I have here described, gives to the latter a number of highlydesirable qualities. Kapok is unusually light in weight and, physicallyconsidered, is of a hollow cylindrical form. The air cavity within eachfiber is largely responsible for the high heat-insulating characteristicof kapok, and the buoyancy of the material in water is also attributedto the hollow form of the fibers although the wax content, resistingabsorption of water, is undoubtedly responsible in part therefor. Infurtherance of this buoyancy, tests conducted with blankets produced inaccordance with the present invention establish that the blankets willfloat in water for upwards of 48 hours and, when rolled, will serve asan eificient substitute for a life preserver. Aside from the low cost,light weight, and a superior ability to insulate against heat transfer,all of which features are highly desirable in substantially any fabricirrespective of the use to which the same is put, the buoyancycharacteristic of a blanket knitted in accordance with the teachings ofthe present invention makes the same almost a specific for use onship-board.

It should perhaps be here stressed that knitting, as distinguished fromweaving is an essential part of the present process, and this is inconsequence of the fact that, in weaving, the movements of the shuttlewill cause kapok fibers within the warp to break and also to be pulledaway from the base material. In a knitting procedure, however, the yarnis not subject to undue flexure and passes back and forth between bothfaces of the knitting to form loops upon both said faces, which loopsareknitted together one with the next adjacent loop. The inlay yarn 1,which contains a large quantity of kapok fibers, pierces these loops.When the kapok fibers, later softened in the manner described, areraised into a multiplicity of surface curls, the fibers pierce theknitting base a plurality of times and are quite effectively lockedagainst slippage. I find that the finished product has considerably lessstretch than is usually found in a knitted product, and which has beenconsidered perhaps the chief defect of an ordinary knitted textile.

The invention will, it is believed, have been clearly understood fromthe foregoing description. The proportion, as between kapok fibers andthe base material, be it cotton. wool or other type of staple fiber, orcombinations thereof, admits of considerable variation and the relativequantities which I have mentioned are not to be considered as implyingany express limitation as to the amount of each which may besatisfactorily used.

What I claim is:

1. The process of producing a textile from staple yarns containing alarge quantity of kapok fibers, which comprises knitting two yarns intoloops on both sides of the fabric to form, in the instance of each suchyarn, 8, ply that interengages with a similar ply formed by the other ofthe two yarns and incorporating, unknit therein, a third yarn as aninlay yarn, and upon completion of the knitting operation softening thekapok fibers and then thread-picking the textile to raise the softenedfibers at several points within their length.

2. The process of producing a textile from staple yarns containing alarge quantity of kapok fibers, which comprises knitting two yarns intoloops on both sides of the fabric to form, in the instance of each suchyarn, a ply that interengages with a similar pl formed by the other ofthe two yarns and incorporating, unknit therein, a third yarn as aninlay yarn, and upon completion of the knitting operation softening thekapok fibers by subjecting the knitted textile to the influence of heatand moisture and then thread-picking the textile to raise the softenedfibers.

3. As a textile, a knit product of which all the contained yarns have anappreciable kapok content and with the kapok fibers raised into surfacecurls closely packed on both faces of the textile.

FRANK Y. NAKAYAMA.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 1,276,909 Heisdorf Aug. 27, 19181,838,663 Dreyfus et a1. Dec. 29, 1931 2,338,792 Whitehead Jan. 11, 1944

